反应烧结制备Si₃N₄基复合材料

【作者】 袁晋；

【导师】 崔崇；

【作者基本信息】 南京理工大学 ， 材料学， 2004， 硕士

【摘要】 本文用气态耗定升温法反应烧结制备了Si₃N₄结合SiC材料和Si₃N₄结合AlN材料，研究了材料的制备工艺，微观组织、气孔率、增重、表面硬度和抗弯强度和反应机理。结果表明，冷等静压成型的材料烧结后性能优于干压成型的材料，SiC颗粒在Si₃N₄基体中分布均匀，试样的气孔率随着SiC含量的增加而增加，材料抗弯强度随着SiC含量的增加有所降低，在SiC含量8％时可以达到最大值141MPa；反应烧结制备AlN结合Si₃N₄时由于烧结的过程中出现液相，容易生成β—Si₃N₄，容易使材料发生熔硅现象，在Al熔点附近延长保温时间，可以形成强度在200MPa的β相Si₃N₄—AlN复合陶瓷。更多还原

【Abstract】 Reaction-sintered SiC/Si3N4 and reaction -sintered A1N /Si3N4 composite material were manufactured by quasi-static temperature-rising craft. The preparation craft, microstructure, pore ratio, surface hardness, bend strength and reaction theorem has been studied and analysed . The result showed the physical property of material molded by hydrostatic pressing is prior to that of material molded by uni-axial pressing. In the SiC/Si3N4 composite material, SiC partical dispersed uniformly in Si3N4 matrix, the pore ratio increased and the bend strength decreased with the increasing mass of SiC, the bend strength of material with 8% SiC is up to 141MPa. The melted silicon and β -Si3N4 could be seen in the A1N/SJ3N4 material because of the liquid phase appearing. Si3N4/AlN material which bend strength was 200Mpa could be prepared if prolong the heat preservation time near Al melting point.更多还原